In my opinion, since you are moving to a new hardware, you have some easier option available if you choose to setup the new machine and move your data there from the old one:

1) zmztozmig: built-in command line utility for zimbra2zimbra migrations, only moves emails.
2) REST API: needs a bit of linux skills but as soon as you get a hold on the basics it'll be better than zmztozming IMHO, as almost any data will be moved.
3) IMAPSYNC: Third-party tool that moves emails through the IMAP protocol.
4) ZeXtras Suite/ZeXtras Mig: Third party tools that moves virtually all data. The part that does the import is paid, but a trial is available and you can use that to migrate.

1), 2) and 4) require Zimbra 6+ - I checkd the download page and you can upgrade to 6.0.16 before migrating.